> We shouldn't be trying to spin downtime as "just a few hours a month." Those hours cost real dollars.

They're also completely irrelevant, you as a customer of a service that is down can lose the same amount of money in a 5 minutes outage or 30 days outage, if you were only relying on this service for one operation that took 1 second and had to happen during the time where the outage happened.

Depending on the service in question, no amount of downtime is acceptable, however unrealistic this is.